#include <iostream>
using namespace std;

#include <unistd.h>
#include <cstring>
int demo()
{
    int a = 100;
    int b = 0;

    int c = a/b;

    return c;
}

int main()
{   
    int pipefd[2];
    pipe(pipefd);

    close(pipefd[0]);
    write(pipefd[1],"hello",5);
    char *ptr = NULL;
    strcpy(ptr,"helloworld");
    while(1)
    {
        cout<<"hello world"<<endl;
        sleep(2);
    }
}